第八届青年地学论坛

Plants experiencing stress could develop ability to reshape their way to improve responding to future stress, called “Ecological Stress Memory” (ESM), which is important for plant acclimation to repeated stresses. Although ESM has been largely reported, it remains unclear whether ESM could improve tree resistance to recurrent stress in subsequent decades. We collected tree-ring data of 1491 trees from 50 long-living juniper forests on the Tibetan Plateau. Through comparing performances of tree radial growth in past sequential growth stresses, we aim to explore the effects of ESM on tree resistance to recurrent stress at a long-time scale. We found that ESM obtained under antecedent stresses and elevate tree resistance to subsequent stress occurred years even decades later. Such positive effects are associated with post-stress recovery. Trees with slow post-stress recovery trajectories show significantly increased tree resistance to subsequent stress. Whereas, trees with extremely fast post-stress recovery trajectories are more susceptible to recurrent stress. Temporary depressive radial growth after antecedent stress might contribute to long-time store of ESM, thereby improve tree resistance to future stronger stress. Incorporating such positive effects of ESM into future Earth system models could improve prediction of forest dynamics and forest ecosystem stabilization under future stress conditions.

 

Dendroecology,Stress memory,Tibetan Plateau